The present invention relates to a hose end sprayer and more particularly to a sprayer of the type which provides for the addition of a concentrate to the liquid being sprayed. The device of the present invention has particular application as a spray washer with detergent feed for washing vehicles, and will be described in this context. It is however not intended to limit the invention to such an application. Indeed, as will be apparent to one skilled in the art from the following description, the present invention has application alternatively to dispensing of liquid or soluble chemicals such as pesticides or plant food additives into a liquid stream being sprayed from a hose end.
Hose end sprayers of the type in question have been previously developed in many different constructions. For example, U.S. Pat. No. 2,908,445 of Schwartz, issued Oct. 13, 1959 describes and illustrates a fountain detergent brush which is useful as an automobile washing brush, in which a soap chamber is mounted, circumscribing a central tube, to slide up and down between operative and inoperative positions on that tube. In operative position, a pair of holes in the tube, communicating with the soap chamber, are opened and water passing through the tube enters the soap chamber and mixes with the soap, so that soap is passed into the water flowing through the tube. In inoperative position these holes are closed so that only pure water, without soap, passes through the tube. Such a device, during operation, provides for a diminished concentration of soap in the chamber, as water mixes with it, so that, towards the end of operation, significantly smaller concentrations of soap are being mixed with the water. This may have a detrimental effect in the washing operation, particularly in those situations where it is desired to have a concentration of soap at the end of the washing operation which is as high as that which existed when the operation commenced. Constructions of sprayers similarly having water co-mingling with the soap in the chamber of the sprayer device are found in Proctor et al U.S. Pat. No. 3,447,753 issued June 3, 1969, Proctor et al U.S. Pat. No. 3,770,205 issued Nov. 6, 1973, and Canadian Pat. No. 1,058,360 of Stoyshin issued July 17, 1979.
Spray devices with chambers holding soap or other chemicals to mix with water, or other liquids passing through associated hoses, in which there is no co-mingling of the water or other liquid with the soap or other chemical in the chamber are found in the prior art as well. For example, Sellers U.S. Pat. No. 3,259,321 issued July 5, 1966 describes and illustrates a canopy type-chamber with collapsible walls mounted on a hose nozzle. By squeezing the walls of the chamber the soap contained in the chamber is forced through a valve opening into a stream of water passing through the nozzle. In Belswenger et al Canadian Pat. No. 1,165,742 issued Apr. 17, 1984, a hose end sprayer is described in which concentrate from a reservoir associated with the spray end nozzle of a hose is drawn from the reservoir by means of suction which is created by the flow of water through a specially constructed chamber at the top of the reservoir and communicating therewith. Koeberich Canadian Pat. No. 652,428 issued Nov. 20, 1962 teaches another such device, this time the reservoir for the concentrate sitting above tubing which is connected to the hose line. A valve associated with the reservoir is opened to permit the concentrate, apparently by gravity, to flow into the water line from the reservoir.
Another patent of general background interest is Knapp U.S. Pat. No. 4,340,179 issued July 20, 1982 which describes and illustrates a cartridge which is connectable to a hose so that water passing through the cartridge from the hose draws nutrients which are then discharged to a lawn through the sprinkler or nozzle at the end of the hose.
It is an object of the present invention to provide a hose end sprayer for car washing and other applications, which will dispense a chemical concentrate from a reservoir without dilution of the concentrate in the reservoir as the device is used. It is a further object of the present invention to provide a novel construction of hose end sprayer which will have particular application in car washing, and which may be used in conjunction with a car wash brush.